What is PSA related to prostate cancer?

Hi coachbarken,

PSA is short for prostate-specific antigen.

"PSA is a protein produced by the cells of the prostate gland. The
prostate-specific antigen test measures the level of PSA in the blood.
When the prostate enlarges, PSA levels typically rise. The levels can
rise due to cancer or benign conditions, according to the National
Cancer Institute."

MedicineNet: Rate of PSA Rise Predicts Prostate Cancer
http://www.medicinenet.com/script/main/art.asp?articlekey=33928

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Screening for prostate cancer by Prostate Specific Antigen (PSA) 

"PSA is a protein produced by the prostate gland. This protein is used
to screen for prostate cancer. A simple blood test can measure PSA
levels, which may rise in the presence of prostate cancer. However,
the test has limitations. PSA can be normal even when cancer is
present. Up to 30% of men with prostate cancer have a normal PSA blood
test, and up to 75% of men with a high PSA blood test do not have
prostate cancer. Finally, elevated PSA levels, even if prostate cancer
is present, cannot distinguish between prostate cancer that would not
cause symptoms or death, and aggressive prostate cancer that could be
fatal."

Palo Alto Medical Foundation: Guidelines for Prostate Cancer
Testing/Prostate Specific Antigen Testing (PSA)
http://www.pamf.org/health/guidelines/psa.html

===================================

"PSA is an ideal marker for prostate cancer because it is basically
restricted to prostate cells. A healthy prostate will produce a stable
amount--typically below 4 nanograms per milliliter, or a PSA reading
of "4" or less--whereas cancer cells produce escalating amounts that
correspond with the severity of the cancer. A level between 4 and 10
may raise a doctor's suspicion that a patient has prostate cancer,
while amounts above 50 may show that the tumor has spread elsewhere in
the body.

Most PSA tests measure "total PSA," or the amount that is bound to
blood proteins. In 1998, FDA approved the Tandem R test, which
measures not only total PSA but another component called "free PSA,"
which floats unbound in the blood. Comparing the two helps doctors
rule out cancer in men whose PSA is mildly elevated from other causes.
A 1995 study in the Journal of the American Medical Association showed
that the free PSA test can reduce unnecessary prostate biopsies by 20
percent in patients with a PSA between 4 and 10."

U.S. Food and Drug Administration: Prostate Cancer
http://www.fda.gov/fdac/features/1998/598_pros.html



Search criteria:
PSA related to "prostate cancer"
"PSA is" "prostate cancer"


I hope the information provided is helpful. If you have any questions
regarding my answer please don?t hesitate to ask before rating it.

Best regards,
Rainbow

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Request for Answer Clarification by coachbarken-ga on 17 Sep 2004 22:41 PDT

Hi Rainbow.
I was interested to find out who are the people answering the
question.  Rainbow is obviously a code name.
One remark:  You did not mention that PSA may rise due to inflammation
or infection of the prostate.  The other point is that the PSA is
abundant in the semen but "leaks" into the blood stream.  You also did
not mention what is the physiological role of the PSA?
I am very curious to find out who are the people answering questions
about prostate cancer?

Thanks
Israel Barken M.D.
Prostate Cancer Research and Education Foundation.

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Clarification of Answer by rainbow-ga on 18 Sep 2004 05:32 PDT

Hello Dr. Barken,

"I am very curious to find out who are the people answering questions
about prostate cancer?"

Rainbow is my Google Answers screen name. We are all researchers and
provide general information only and do not take the place of a
medical professional.

Please read the disclaimer at the bottom of this page which includes the following:

"Answers and comments provided on Google Answers are general
information, and are not intended to substitute for informed
professional medical, psychiatric, psychological, tax, legal,
investment, accounting, or other professional advice."


Your question was what the relation of PSA is to prostate cancer. I
based my research on that question and answered it.

"You did not mention that PSA may rise due to inflammation or
infection of the prostate.  The other point is that the PSA is
abundant in the semen but "leaks" into the blood stream."

Had you asked what the effects are of PSA with an infection of the
prostate, I would have researched and answered that question.


"You also did not mention what is the physiological role of the PSA?"

Had you asked what is the physiological role of the PSA, I would have
researched and answered that question.


The amount of information on PSA is enormous. For the price you
offered, I based my research on the specific question and did not
expand into other areas. Please note the Google Answers pricing
guidelines here:
http://answers.google.com/answers/pricing.html

I hope this answers you questions. If you have any more questions,
please don't hesitate to ask and I will do my best to further assist
you.

Best regards,
Rainbow

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Request for Answer Clarification by coachbarken-ga on 18 Sep 2004 17:09 PDT

Fair enough.
I agree with you.
You gave a good an answer.
As appreciation can I pay $20?

I really appreciate your service.
Take care
Best wishes
Israel Barken M.D

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Clarification of Answer by rainbow-ga on 20 Sep 2004 04:03 PDT

Hi Dr. Barken,

I'm glad I was able to help. Thank you very much for the rating and generous tip.

Best wishes,
Rainbow

I recieved a prompt response.  The response was very satisfactory.